Cutting tool



J. L. WHITE CUTTING TOOL Nov. 23,1948.

lINVENTOR.

U/Xi/ Patented Nov. 23, 1948 UNITED STATES PATENT OFFICE.

CUTTING 'rooL John L. White, Dallas, Tex.

Application March 23, 1945, Serial No. 584,417

1 Claim. 1

This invention relatesto tools for cutting sheet material and it has particular reference to a cutting tool especially adaptable for use with a portable power unit, designed to drive the tools of various detachable sub-units.

The principal object of the invention is to provide -a cutting tool which isextremely simple in construction, having but two moving parts which are easily and quickly removed or replaced in the stock or shank for-convenience of repair or replacement and further, the provision of a tool who-se flexibility in adaptation, renders it useful under any and all conditions where a more expensive cutting tool is employed.

Another object of the invention is to provide a tool of the character set forth having an integral foot and a cutter shank and combining a novel form of reciprocating medium for the cutter mounted in the shank, the said medium consisting of a lateral driving shaft having an 01T- centered pin rotatably disposed in a transverse slot in the cutter plunger. Moreover, the curvilinear formation of the work engaging foot is such that the latter embraces the cutting area at a point spaced below the shank, to provide a supporting surface for the work being subjected to the action of the cutter; to guide the work as it is being cut away from the cutter and to adequately reinforce the tool about the cutting area.

Still another object of the invention is to provide a sheet material cutting tool in which the work supporting surface has embedded therein an adjustable shear plate, the adjustability of this plate enabling the latter to be rotated to new positions when the operative edge has become worn or nicked.

With the foregoing objects as paramount, the invention has further reference to certain features of accomplishment which will become apparent as the description proceeds, taken in connection with the accompanying drawings wherein:

Figure 1 is a perspective view of a tool constructed according to the present invention.

Figure 2 is an elevational view from the front of the tool, in vertical section.

Figure 3 is an elevational view rotated 90 from Figure 2 and in vertical section on line 3-3 on Figure 2.

Figure 4 is a bottom plan view of the tool, and

Figure 5 is a combined showing of a modified form of cutting plunger in fragmentary perspective and in transverse cross-section.

Continuing with a more detailed description of the drawing, reference numeral I0 denotes generally the body of the tool, made up of a the plunger I4, through which work is introduced into the opera-tive` area of the cutter I5, formed on the lower end of the plunger. It will be observed that the foot I3 is slightly inclinedin relation to the longitudinal axis of the shank II for convenience in manipulating the tool in relationV to the work. At the juncture between the foot and the shank, the under surface a of the foot curves downwardly. This provision insures deflection of a severed portion of the material away from that part of the material supported upon the planoV work supporting surface b.

The plunger i4 is reciprocably mounted in a bore extending axially through the shank II and adjacent its upper end, there is provided a transverse slot I6 into which extends a pin I'I carried by and offset in relation to the axial center of the drive shaft I8. It Will be noted that the width of the slot I6 is such as to allow but slight clearance between its walls and the pin I'I but its length is greater than the diameter of this pin. Obviously, when the shaft I8 is rotated, the eccentric movement of the pin I1 constrains the plunger I4 to reciprocate and the degree of displacement thereof is equal to the degree of oiset of the pin and this ratio may be varied in accordance with displacement requirements of the plunger. i

The boss I2 of the shank II `is interiorly threaded to receive the threaded nipple I9 of the collar 20. Both the nipple I9 and collar 20 are cored to receive the enlarged portion of the drive shaft identied by reference numeral I8 in Figure 3 but this core terminates short of the end of the collar 20, providing a shoulder c which takes the thrust of the said enlarged portion I8 of the drive shaft and limits longitudinal displacement of the drive shaft. The portion I8, the pin I'I and the spindle 2| are turned from a single piece of material and this piece as well as the plunger I4 is case hardened to minimize frictional wear.

It is intended that the spindle 2I be secured in and driven by the chuck of a conventional electric hand drill but it is apparent that any other form of drive may be applied to the spindle 2l 3 and for that matter, the tool may be stationarily mounted so that the spindle 2I may be driven by a belt or flexible shaft as desired. Provision is made through the holes 22 in the shank II and collar 20 for lubricating the plunger I4 and shaft I8 respectively.

Referring again to the foot I3, this member has a recess 23 which communicates with the open area next adjacent the operative end of the plunger Ill or Ispecifically the cutter I5. 4This recess may be of any desired shapebut is preferably circular and receives a conformably shaped shear plate 24, held in place by screw 25 which enters the same through the foot I3 from the bottom. Through this provision, any impairment of the operative edge of the shear plate may be corrected by rotating the plate to a new positio-n or by grinding a new'edge on the plate. Moreover, by virtue of the plurality of shearing edges spaced about the plate 24, provision is made for cutting materials of various gauges, it being pointed out that the' relative spacing between the cutter I5 and shearing edge of the plate may be varied by changing the position of the plate in the recess 23. .Should the cutter I5 become worn or damaged, it is a simple matter to back off the collar 2i] to withdraw the pin II from the slot I6 in the plunger lli and remove the latter from the shank. It may then be reground or replaced by a new cutter at small cost.

As va modication of the cutter plunger I4, a construction as shown in Figure 5 is provided. By grinding a radiusy d in the shank ld immediately above the integrally formed cutter blade I5a, it is possible `tomove the tool-in an arcuate course 4, in cutting to the left as expeditiously as to the right, the said radius removing obstruction to the work, otherwise presented by the stock of the plunger directly above the shear blade.

Maniiestly, the construction as shown and described is capable of some modification and such modiication as may be construed to fall within the scope and meaning of the appended claim is also considered to be Within the spirit and intent'of ,the invention.

What is claimed is: l

In a metal cutting tool, a reciprocable plunger therefor provided with a shear blade on one end and whose shank is ground to produce a Work Jdeilecting radius originating approximately in line withand above the center of the shear blade and extending in a gradual curve about the axis of said plunger to a terminus at approximately from its points of origin.

JOHN L. WHITE.

`REFERENCES CITED The following references are of record in the le .of -this patent:

UNITED STATES PATENTS Number Name Date 705,069 Grall July 22, l1902 1,342,240 Walter June .1, '1920 .1,737,884 Hexdall DeC. 3, 1929 .1,922,846 Gray Aug. 15, 1933 v2,125,556 Gleich Aug. 2, 1938 .2,226,241 Gray Dec. 24, 1940 2,256,779 McHenry Sept. 23, 1941 .2,268,728 Toop Jan. 6, 194.2 

